Description
A denial of service flaw was found in dovecot before 2.2.34. An attacker able to generate random SNI server names could exploit TLS SNI configuration lookups, leading to excessive memory usage and the process to restart.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| The Dovecot Project | dovecot | before 2.2.34 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | dovecot | 1:2.2.34-1 | — |
| Debian 13 | dovecot | 1:2.2.34-1 | — |
| Debian 12 | dovecot | 1:2.2.34-1 | — |
| Debian 9 | dovecot | 1:2.2.27-3+deb9u2 | DSA-4130-1 |
| Debian 8 | dovecot | 1:2.2.13-12~deb8u4 | DSA-4130-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 7 | dovecot | 1:2.1.7-7+deb7u2 | DLA-1333-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | dovecot | 1:2.2.22-1ubuntu2.7 | USN-3587-1 |
| Ubuntu 14.04 LTS | dovecot | 1:2.2.9-1ubuntu2.4 | USN-3587-1 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP3 | dovecot22 | 2.2.31-19.11.1 | SUSE-SU-2018:2632-1 |
| SLES 12 SP2 | dovecot22 | 2.2.31-19.11.1 | SUSE-SU-2018:2632-2, SUSE-SU-2018:2632-1 |
| SLES 12 SP1 | dovecot22 | 2.2.31-19.11.1 | SUSE-SU-2018:2632-1 |
| SLES 12 | dovecot22 | 2.2.31-19.11.1 | SUSE-SU-2018:2632-1 |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 12 SP3 | dovecot22 | 2.2.31-19.11.1 | SUSE-SU-2018:2632-1 |
| SLES for SAP 12 SP2 | dovecot22 | 2.2.31-19.11.1 | SUSE-SU-2018:2632-1 |
| SLES for SAP 12 SP1 | dovecot22 | 2.2.31-19.11.1 | SUSE-SU-2018:2632-1 |
| SUSE OpenStack Cloud 7 | dovecot22 | 2.2.31-19.11.1 | SUSE-SU-2018:2632-1 |
| SUSE Enterprise Storage 4 | dovecot22 | 2.2.31-19.11.1 | SUSE-SU-2018:2632-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | dovecot23 | 2.3.16-1.6 | openSUSE-SU-2024:10726-1 |
| openSUSE Tumbleweed | dovecot24 | 2.4.0-1.1 | openSUSE-SU-2025:14715-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | dovecot | 2.3.1-r0 | — |
| Alpine v3.23 | dovecot | 2.3.1-r0 | — |
| Alpine v3.22 | dovecot | 2.3.1-r0 | — |
| Alpine v3.21 | dovecot | 2.3.1-r0 | — |
| Alpine v3.20 | dovecot | 2.3.1-r0 | — |
Show 13 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | dovecot | 2.3.1-r0 | — |
| Alpine v3.18 | dovecot | 2.3.1-r0 | — |
| Alpine v3.17 | dovecot | 2.3.1-r0 | — |
| Alpine v3.16 | dovecot | 2.3.1-r0 | — |
| Alpine v3.15 | dovecot | 2.3.1-r0 | — |
| Alpine v3.14 | dovecot | 2.3.1-r0 | — |
| Alpine v3.13 | dovecot | 2.3.1-r0 | — |
| Alpine v3.12 | dovecot | 2.3.1-r0 | — |
| Alpine v3.11 | dovecot | 2.3.1-r0 | — |
| Alpine v3.10 | dovecot | 2.3.1-r0 | — |
| Alpine v3.9 | dovecot | 2.3.1-r0 | — |
| Alpine v3.8 | dovecot | 2.3.1-r0 | — |
| Alpine v3.7 | dovecot | 2.2.34-r0 | — |
Advisories 8
- USN-3587-1 dovecot vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- DSA-4130-1 dovecot - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-1333-1 dovecot - security update Debian Security (DSA / DLA) · Mar 9, 2026
- SUSE-SU-2018:2632-1 Security update for dovecot22 SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2025:14715-1 dovecot24-2.4.0-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:2632-2 Security update for dovecot22 SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:10726-1 dovecot23-2.3.16-1.6 on GA media SUSE / openSUSE Security Updates · May 7, 2025
- WID-SEC-2025-0244 Dovecot: Mehrere Schwachstellen ermöglichen Denial of Service BSI CERT-Bund (WID) · Feb 2, 2025
References
- USN-3587-1 vendor-advisory
- [oss-security] 20180301 Dovecot Security Advisory: CVE-2017-15130 TLS SNI config lookups are inefficient and can be used for DoS mailing-list
- [debian-lts-announce] 20180331 [SECURITY] [DLA 1333-1] dovecot security update mailing-list
- DSA-4130 vendor-advisory
- USN-3587-2 vendor-advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1532356
- [dovecot-news] 20180228 v2.2.34 released mailing-list